Chord notation is a form of musical notation which is especially useful for notating jazz or popular music. Rather than indicating all the notes to be played, in chord notation only the melody is indicated precisely. The accompaniment is indicated as a series of chord labels indicating what type of chord is to be played at different points of the melody. Chord notation allows the same sheet music to be played on multiple different instruments, since the player of each instrument can interpret the chord in a way suitable for the player's own instrument. Chord notation can also be simpler to read than a fully scored notation, since fewer notes need to be read at once. Another advantage of chord notation is that the chord progressions provide a basis for jazz improvisation.
To read chord notation, the player needs to know how to play the types of chords indicated on the music. As there are twelve possible root notes for chords, and hundreds of different types of chords (especially in jazz music, where unusual chords are sometimes used), there are thousands of possible chords. For a keyboard player, chord books are available which list many diagrams of the keyboard, each diagram having certain keys highlighted to indicate the notes that make up a particular chord. Unfortunately, it is inconvenient to browse through the book trying to find the particular chord desired to play a particular part of a musical piece (especially when the piece of music requires, say, ten or twenty different types of chords). Once the desired chord is found, the player then needs to keep looking backwards and forwards between the book and the keys of the keyboard to work out which notes should be played for the desired chord. Moreover, as each chord is indicated separately in the chord book, the relationship between different types of chords, or different chords of a single type, may not be apparent to the user of the chord book.
Similarly, for other musical patterns such as scales or arpeggios, books are available indicating how to play these musical patterns. However, often scale and arpeggio books indicate these musical patterns using full musical notation, so a player who cannot read musical notation is unable to play the scales and arpeggios indicated.
U.S. Pat. No. 3,350,973 describes a music chord finder device for a keyboard. The device comprises a plate which can be placed next to the keys of the keyboard. The outer surface of the plate carries various markers which are spaced apart to indicate the keys of the keyboard required for playing certain chord types. By sliding the plate up and down the keyboard, different chords can be indicated by the markers. However, the music chord finder device can be awkward to use because the markers are provided in multiple rows one above the other on the surface of the plate, and so it is not always clear which markers correspond to which chords. Also, there is only room for a limited number of types of chords on the outer surface of the plate.
The present technique seeks to address these problems and provide a device for indicating many different musical patterns in a compact form, in a way that is easy to understand for the user.